Hitherto, various types of photo-curable or heat-curable resin compositions have been well known.
The heat-curable resin compositions have been used in a wide range of uses such as materials for molding, materials for injection molding, coatings and adhesives, in spite of that the resin has a disadvantage of accompanying considerable cubical shrinkage in curing process.
On the other hand, the photo-curable resin compositions, which can be cured by an active energy beam such as ultraviolet rays or electronic rays, have been widely used in various fields such as, for example, inks, coatings, varnishes, encapsulating materials, photo-resist materials and film materials for protecting.
Recently, there have been developed photo-curable resin compositions, with which a complicated model or various articles having a fixed shape for preparing a casting die or profiling processes can be manufactured by irradiating an active energy beam.
Particularly, a photo-curable resin composition is more advantageous in comparison with a heat-curable resin composition, because of (1) the short curing period of time, (2) curability in low temperatures and (3) unnecessary or small amount of solvents resulting in material saving and further low pollution in surroundings.
Accordingly, it has been actively developed in various fields.
For example, a polyester acrylate, a polyether acrylate, an epoxy acrylate and or a polyurethane acrylate, etc., which have at least two acrylic or methacrylic groups, have been typically supplied on a commercial basis.
Recently, such acrylate resin compositions have been widely used in various fields such as, for example, as coating compositions for wooden products or paper, etc., an reactivity modifier for thermoplastic resins such as polyvinyl chloride resins, an anaerobic adhesive, or as a resin for a photoresist, etc., in addition to the above-described uses.
However, the above-described acrylate coatings do not have sufficient curing velocity, hardness, ductility and outdoor durability, etc., and novel materials having well-balanced properties have been desired.
The present inventors have found that the drawbacks of prior art materials can be avoided by the use of a polyfunctional (meth)acrylate composition having cyclohexane units and ether groups in the main molecular chain of the molecule, and (meth)acrylic groups as a side chain for the above-described uses.